The LaserDisc i21 26” rim is the ideal rim for today’s All Mountain abuse. Its 21-millimeter inner rim width adds strength and accommodates a wide range of tires from 2.0″ XC tires to 2.5″ DH treads. The LaserDisc i21 rim features I-Beam technology, Unbendium Bulge and GBS. The I-Beam was pioneered by WTB in 1994. This distinctive, centrally located vertical support counteracts spoke loads and provides torsional rigidity. The Unbendium Bulge is an additional band of aluminum added to the rim sidewall that improves torsional, radial and lateral strength. This rib, which replaces the braking surface, provides an impressive boost in rigidity with a negligible difference in weight. WTB’s proprietary GBS (Global Bead System) design utilizes deeper grooves for the bead seats as well as two raised lips that lock the tire’s beads into place on the rim. GBS features superior tire retention and greatly reduces the chance of “burping” the tire off the rim in heavy lateral loading.